Clinical Focus

  • Neonatal Cleft Lip and Palate - Non-surgical Nasal Alveolar Molding
  • Neonatal Obstructive Sleep Apnea / Pierre Robin Sequence - Non-surgical Orthodontic Airway Plate
  • Infant Orthodontics - Airway, Molding, and Feeding
  • Non-surgical and Surgical Orthodontics for Obstructive Sleep Apnea
  • Non-surgical and Surgical Orthodontics for Facial Reconstructive Surgery
  • 3D Craniofacial Imaging and Airway Analysis
  • Orthodontics

Administrative Appointments

  • Director, Craniofacial & Sleep Orthodontic Clinic (2019 - Present)
  • Lead Orthodontist, Craniofacial Orthodontic Clinic (2016 - 2019)

Honors & Awards

  • National Dental Honor Society, Omicron-Kappa-Upsilon (2004)

Professional Education

  • Fellowship, Clinical Center, National Institutes of Health (NIH) / National Institute of Dental and Craniofacial Research (NIDCR), Bethesda, MD (2008)
  • Board Certification, American Board of Orthodontics (2008)
  • Post-Graduate Residency & MS, Department of Orthodontics and Dentoalveolar Orthopedics, Masters in Science, University of Alabama in Birmingham, Birmingham, AL (2007)
  • DMD, Graduate School of Dental Medicine, University of Pennsylvania, Philadelphia, PA (2004)
  • DDS, Combined Undergraduate School of Natural Sciences & Graduate School of Dental Surgery, Seoul National University, Seoul, South Korea (2002)


All Publications

  • Use of C-Tube Microplates for Controlling the Vertical Dimension During Maxillary Incisor Intrusion. Journal of clinical orthodontics : JCO Noh, M. K., Seo, K. W., Choo, H., Chung, K. R., Kim, S. H. 2019; 53 (7): 414–25

    View details for PubMedID 31648217

  • The biocreative strategy. Part 4: Molar distalization in nonextraction treatment. Journal of clinical orthodontics : JCO Chung, K. R., Kim, Y., Choo, H., Kim, S. H., Nelson, G. 2018; 52 (9): 462–75

    View details for PubMedID 30256221

  • Non-extraction correction of Class II malocclusion using Biocreative Therapy Skeletal Anchorage in Orthodontic Treatment of Class II Malocclusion Chung, K., Choo, H., Kim, S. Mosby Elsevier. 2014; 1: 239–243
  • Modified Technique of Presurgical Infant Maxillary Orthopedics for Complete Bilateral Cleft Lip and Palate PLASTIC AND RECONSTRUCTIVE SURGERY Choo, H., Maguire, M., Low, D. W. 2012; 129 (1): 244–48


    This article introduces technical modifications to the conventional presurgical infant maxillary orthopedics device for newborns with complete bilateral cleft lip and palate, providing procedural simplicity and efficiency as well as therapeutic efficacy. The modifications incorporate a wax block-out on the stone model prior to device fabrication in a manner that the need for periodic acrylic addition and removal is not required, and thus eliminates the risk of natural maxillary growth restriction during infant maxillary orthopedics treatment. The premaxilla is completely excluded from the acrylic palatal plate and is repositioned primarily by the bilateral labial tape alone. In addition, nasal stent wires are installed on the same day of the palatal plate delivery to establish a tripod-like retention mechanism for the intraoral device to be able to replace the conventional mechanical lock-type retention methods. Applying these modifications, infant maxillary orthopedics treatment objectives for bilateral cleft lip and palate can be successfully achieved within 8 weeks of treatment, and the definitive primary cleft lip repair can be performed within 3-4 months of infant maxillary orthopedics treatment at our Center.

    View details for DOI 10.1097/PRS.0b013e318230c84c

    View details for Web of Science ID 000298857100097

    View details for PubMedID 22186513

  • Modified Technique of Presurgical Infant Maxillary Orthopedics for Complete Unilateral Cleft Lip and Palate PLASTIC AND RECONSTRUCTIVE SURGERY Choo, H., Maguire, M., Low, D. W. 2012; 129 (1): 249–52


    This article introduces a modified device fabrication and facial taping method that increases the efficiency and efficacy of presurgical infant maxillary orthopedic therapy for babies born with complete cleft lip and palate. Interarch and intra-arch relationships of the maxillary and mandibular dental arches were evaluated on mounted stone models before and after treatment. The palatal plate device was custom-fabricated in a manner that bypassed the need for periodic acrylic addition and removal, thereby eliminating the risk of natural maxillary growth restriction during therapy. Elastic labial tapes were fabricated and applied in a configuration that mimicked normal function of the orbicularis oris muscle. A nasal stent wire was utilized from the initiation of therapy to enhance intraoral retention and stability of the device. Examples of infants undergoing a unilateral complete cleft lip and palate treatment protocol are presented. Treatment objectives were achieved within 7 to 8 weeks of therapy for patients who had an initial alveolar cleft size more than 10 to 12 mm. The modified protocol of presurgical infant maxillary orthopedic therapy is an effective and efficient treatment modality in reversing the pre-existing orofacial dysmorphism by redirecting the infant's natural growth.

    View details for DOI 10.1097/PRS.0b013e318230c8bb

    View details for Web of Science ID 000298857100098

    View details for PubMedID 22186514

  • Treatment outcome analysis of speedy surgical orthodontics for adults with maxillary protrusion AMERICAN JOURNAL OF ORTHODONTICS AND DENTOFACIAL ORTHOPEDICS Choo, H., Heo, H., Yoon, H., Chung, K., Kim, S. 2011; 140 (6): E251–E262


    The purposes of this study were to quantify the treatment outcomes of speedy surgical orthodontic treatment for adults with maxillary protrusion and to identify the key factors influencing the efficacy of speedy surgical orthodontic biomechanics.Twenty-four adults with maxillary or bimaxillary protrusion were treated with speedy surgical orthodontics, including maxillary perisegmental corticotomy followed by the orthopedic en-masse retraction against C-palatal miniplate anchorage. The average total treatment time was 20 months (range, 11-42 months). Lateral cephalograms were taken at pretreatment, just after the perisegmental corticotomy, and at posttreatment to evaluate the skeletal and soft-tissue changes. The Pearson correlation analysis was used to identify the relationships between hard-tissue, soft-tissue, and perisegmental corticotomy variables.The maxillary central incisors were retracted by 9.19 ± 0.31 mm and retroclined by 19.73° ± 1.17°. The change of the maxillary alveolar ridge angle was 13.97° ± 1.04°. The extrusion tendency of the retracted maxillary incisors was minimal, measured as 1.17 ± 0.36 mm. The width of the buccal corticotomy showed statistically significant correlations with the angular change of the maxillary central incisors and the maxillary alveolar ridge angle. The retrusion of the maxillary central incisors and the maxillary alveolar ridge angle were the 2 hard-tissue variables that most closely correlated with retrusion of the upper lip.Speedy surgical orthodontic treatment can be an effective modality for adults with severe maxillary protrusion.

    View details for DOI 10.1016/j.ajodo.2011.06.029

    View details for Web of Science ID 000297994200001

    View details for PubMedID 22133959

  • The effects of different pilot-drilling methods on the mechanical stability of a mini-implant system at placement and removal: a preliminary study KOREAN JOURNAL OF ORTHODONTICS Cho, I., Choo, H., Kim, S., Shin, Y., Kim, D., Kim, S., Chung, K., Huang, J. C. 2011; 41 (5): 354–60
  • Histologic assessment of the biological effects after speedy surgical orthodontics in a beagle animal model: a preliminary study KOREAN JOURNAL OF ORTHODONTICS Kim, H., Lee, Y., Park, Y., Chung, K., Kang, Y., Choo, H., Kim, S. 2011; 41 (5): 361–70
  • Atypical orthodontic extraction pattern managed by differential en-masse retraction against a temporary skeletal anchorage device in the treatment of bimaxillary protrusion AMERICAN JOURNAL OF ORTHODONTICS AND DENTOFACIAL ORTHOPEDICS Chung, K., Choo, H., Lee, J., Kim, S. 2011; 140 (3): 423–32


    This report introduces an innovative treatment approach of selecting atypical and unconventional teeth for orthodontic extraction without compromising the quality of treatment outcomes by using temporary skeletal anchorage devices in patients with bimaxillary protrusion. Both patients introduced in this report had solid Class I molar relationships with bimaxillary anterior protrusion without facial or dental midline asymmetry. Their chief concerns were significant facial convexity, which conventionally requires the extraction of all 4 first premolars. However, 3 second premolars and 1 first premolar were removed in the first patient, and 2 second premolars and 2 first premolars were removed in the second patient. All second premolars extracted had previously had root canal treatment and large prosthodontic restorations, which resulted in a compromised short lifespan of the teeth relative to the natural dentition. To manage these cases of asymmetric extraction space in a symmetric dental and skeletal environment, 2 mini-implants were placed in the posterior maxillary interradicular spaces, 1 on each side. Despite the unusual asymmetric extraction of teeth, superimposition of the pretreatment and posttreatment cephalometric tracings shows excellent treatment outcomes of facial convexity reduction by asymetric maximum retraction of the anterior teeth with no change in the molar relationships.

    View details for DOI 10.1016/j.ajodo.2009.08.036

    View details for Web of Science ID 000294678700031

    View details for PubMedID 21889088

  • Advanced Applications of Cone Beam Computed Tomography in Orthodontics Seminars in Orthodontics Mah, J. K., Liu, Y., Huang, J. C., Choo, H. 2011; 17 (1): 57-71
  • Novel application of the 2-piece orthodontic C-implant for temporary crown restoration after orthodontic treatment. American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics Jeong, D. M., Choi, B., Choo, H., Kim, J. H., Chung, K. R., Kim, S. H. 2011; 140 (4): 569–79


    This article reports the use of an orthodontic mini-implant for a temporary crown restoration in a small edentulous space after limited orthodontic treatment.Two clinical cases are presented: a 23-year-old woman and a 14-year-old boy. In the adult patient, a 2-piece orthodontic C-implant (Cimplant, Seoul, Korea) was placed in a 3-mm wide edentulous space to build up a temporary crown restoration after a short orthodontic treatment to regain space for a missing mandibular right permanent lateral incisor. In the boy, a C-implant was placed in the space resulting from an avulsed maxillary right permanent lateral incisor to prevent aggressive alveolar bone resorption after dental trauma. Both patients were followed for more than 4 years of retention to evaluate the stability of the temporary crown restoration built up on the orthodontic mini-implants.Both patients had successful long-term results, confirmed by clinical and radiographic examinations. Both were pleased with the results and plan to retain the orthodontic mini-implant temporary crown restoration until they are ready for a permanent restoration later.A 2-piece orthodontic C-implant system can be used to maintain edentulous space after active orthodontic treatment.

    View details for DOI 10.1016/j.ajodo.2009.10.051

    View details for PubMedID 21967946

  • Class III Correction Using Biocreative Therapy (C-Therapy) Seminars in Orthodontics Chung, K., Kim, S., Choo, H. 2011; 17 (2): 108-123
  • Replacing a failed mini-implant with a miniplate to prevent interruption during orthodontic treatment. American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics Lee, J. H., Choo, H., Kim, S. H., Chung, K. R., Giannuzzi, L. A., Ngan, P. 2011; 139 (6): 849–57


    When mini-implants fail during orthodontic treatment, there is a need to have a backup plan to either replace the failed implant in the adjacent interradicular area or wait for the bone to heal before replacing the mini-implant. We propose a novel way to overcome this problem by replacement with a miniplate so as not to interrupt treatment or prolong treatment time.The indications, advantages, efficacy, and procedures for switching from a mini-implant to a miniplate are discussed. Two patients who required replacement of failed mini-implants are presented. In the first patient, because of the proximity of the buccal vestibule to the mini-implant, it was decided to replace the failed mini-implant by an I-shaped C-tube miniplate. In the second patient, radiolucencies were found around the failed mini-implants, making the adjacent alveolar bone unavailable for immediate placement of another mini-implant. In addition, the maxillary sinus pneumatization was expanded deeply into the interradicular spaces; this further mandated an alternative placement site. One failed mini-implant was examined under a scanning electron microscope for bone attachment.Treatment was completed in both patients after replacement with miniplates without interrupting the treatment mechanics or prolonging the treatments. Examination under the scanning electron microscope showed partial bone growth into the coating pores and titanium substrate interface even after thorough cleaning and sterilization.Replacement with a miniplate is a viable solution for failed mini-implants during orthodontic treatment. The results from microscopic evaluation of the failed mini-implant suggest that stringent guidelines are needed for recycling used mini-implants.

    View details for DOI 10.1016/j.ajodo.2009.08.032

    View details for PubMedID 21640893

  • Timely relocation of mini-implants for uninterrupted full-arch distalization AMERICAN JOURNAL OF ORTHODONTICS AND DENTOFACIAL ORTHOPEDICS Chung, K., Choo, H., Kim, S., Ngan, P. 2010; 138 (6): 839–49


    This report describes a novel concept of relocating orthodontic mini-implants during dental distalization to provide unrestricted distal movement of the full maxillary dentition. The patient was an 18-year old Korean woman with a full-step Class II Division 1 malocclusion and mandibular deficiency. Mini-implants were initially placed bilaterally between the maxillary second premolar and the first molar. Sliding jigs were used to distalize the maxillary first and second molars. After the maxillary molars were distalized to a Class I molar relationship, the mini-implants were removed and immediately relocated distally to provide space for retraction of the anterior teeth. The occlusion was completed with Class I molar and canine relationships with optimal overjet and overbite. The 2-year posttreatment records showed a stable treatment with retention.

    View details for DOI 10.1016/j.ajodo.2009.02.035

    View details for Web of Science ID 000284940000046

    View details for PubMedID 21130344

  • Practical applications of cone-beam computed tomography in orthodontics JOURNAL OF THE AMERICAN DENTAL ASSOCIATION Mah, J. K., Huang, J. C., Choo, H. 2010; 141 (10): 7S–13S


    Comprehensive visualization and records of the craniofacial complex have been goals in orthodontic imaging. These tasks have been performed by means of plaster, photographs and radiographs. These approaches have evolved across time, and cone-beam computed tomography (CBCT) has emerged as a comprehensive imaging modality for orthodontics.The authors provide a practical guide for applying CBCT in orthodontics, with an emphasis on situations in which conventional imaging is limited. These situations include dental development, limits of tooth movement, airway assessment, craniofacial morphology and superimposition.Complexities of the craniofacial complex, dentition and airway present challenges in obtaining conventional images. CBCT has image-fidelity advantages over conventional imaging that can lead to improved visualization.CBCT is changing orthodontics with respect to clinically assessing patients and is evolving with respect to diagnosis, clinical techniques and outcomes.The clinical value proposition of CBCT is to describe craniofacial anatomy accurately and provide comprehensive information regarding anatomical relationships and individual patient findings for improved diagnosis, treatment planning and prognostication.

    View details for DOI 10.14219/jada.archive.2010.0361

    View details for Web of Science ID 000282847600002

    View details for PubMedID 20884934

  • Distalization of the mandibular dentition with mini-implants to correct a Class III malocclusion with a midline deviation AMERICAN JOURNAL OF ORTHODONTICS AND DENTOFACIAL ORTHOPEDICS Chung, K., Kim, S., Choo, H., Kook, Y., Cope, J. B. 2010; 137 (1): 135–46


    This article describes the orthodontic treatment for a young woman, aged 23 years 5 months, with a Class III malocclusion and a deviated midline. Two orthodontic mini-implants (C-implants, CIMPLANT Company, Seoul, Korea) were placed in the interdental spaces between the mandibular second premolars and first molars. The treatment plan consisted of distalizing the mandibular dentition asymmetrically and creating space for en-masse retraction of the mandibular anterior teeth. C-implants were placed to provide anchorage for Class I intra-arch elastics. The head design of the C-implant minimizes gingival irritation during orthodontic treatment. Sliding jigs were applied buccally for distalization of the mandibular posterior teeth. The active treatment period was 18 months. Normal overbite and overjet were obtained, and facial balance was improved.

    View details for DOI 10.1016/j.ajodo.2007.06.023

    View details for Web of Science ID 000274393400021

    View details for PubMedID 20122441

  • Cone-beam computed tomography evaluation of orthodontic miniplate anchoring screws in the posterior maxilla. American journal of orthodontics and dentofacial orthopedics : official publication of the American Association of Orthodontists, its constituent societies, and the American Board of Orthodontics Kim, G. T., Kim, S. H., Choi, Y. S., Park, Y. J., Chung, K. R., Suk, K. E., Choo, H., Huang, J. C. 2009; 136 (5): 628.e1–10; discussion 628–29


    The purposes of this study were to evaluate the actual postplacement positions of orthodontic miniplate anchoring screws (MPAS) and to determine the risk factors for their failure and iatrogenic effects on the intraoral structures.Three-dimensional cone-beam computed tomography images were generated to examine 31 orthodontic miniplates and their MPAS (diameter, 1.5 mm; length, 4 mm), which showed good clinical stability 6 months after placement in the posterior maxilla of 18 patients. The cone-beam computed tomography data were analyzed with analysis of variance (ANOVA) statistics to evaluate the difference of placement depth and vertical distance of the MPAS from the cementoenamel junction to the center of the screw. The Fisher exact test was used to determine differences in MPAS position, root proximity, and sinus penetration.The mean placement depth of the MPAS was 2.48 mm with no significant difference relative to their position. Twenty-six (of 74) MPAS were placed in the dentition area. Of these 26, 14 were placed in interdental spaces, and the other 12 followed the direction of the roots. Nine MPAS showed root proximity, and 7 MPAS had root penetration, all of which were placed in the central position of the miniplate. Thirty-nine MPAS penetrated the sinus, indicating a low interrelationship between placement depth and cortical bone thickness of the sinus.Miniplates were successfully retained by MPAS even with less-than-ideal placement. Root contact and proximity of MPAS seem to have minimal effects on the successful stabilization of miniplates. Pertinent guidelines should, however, be followed during MPAS placement to minimize the risk of damage to adjacent roots.

    View details for DOI 10.1016/j.ajodo.2009.02.023

    View details for PubMedID 19892272

  • Anterior torque control using partial-osseointegrated mini-implants: biocreative therapy type II technique. World journal of orthodontics Chung, K. R., Kim, S. H., Kook, Y. A., Choo, H. 2008; 9 (2): 105–13


    To show the clinical application of surface-treated mini-implants (C-Implants) in managing an anterior torque control during en masse retraction of anterior dentition.Nickel-titanium archwire with reverse curve of Spee, which is directly engaged in the hole of C-Implants, and severe curve of Spee can be overlaid on anterior segmented archwires to generate anterior torque on the anterior dentition to resist lingual tipping during en masse retraction. This treatment mechanics is called the biocreative therapy type II technique. The characteristics and procedure of the type II technique for treating maximum anchorage using the C-Implants is shown with case reports of treated patients. The biomechanics and a comparison to the type I technique of this treatment are also described.The authors show the clinical application of type II technique during anterior retraction on various cases, possible indications, and simplicity of the mechanics.Biocreative therapy, which implements partial-osseointegrated mini-implants, presents a novel therapeutic approach in orthodontics. A technique of intrusion overlay archwires for anterior torque control also simplifies the design of orthodontic appliances while eliminating unwanted side effects, such as vertical changes on posterior anchorage teeth during en masse retraction.

    View details for PubMedID 18575304

  • Double-archwire mechanics using temporary anchorage devices to relocate ectopically impacted maxillary canines. World journal of orthodontics Kim, S. H., Choo, H., Hwang, Y. S., Chung, K. R. 2008; 9 (3): 255–66


    This case report introduces a novel double archwire mechanics concept using orthodontic mini-implants and a miniplate to relocate ectopically impacted maxillary canines in a 14-year-old female with a Class III subdivision left malocclusion. The objective of this orthodontic treatment was to salvage the maxillary lateral incisors so they could be used for conservative restorations upon completion of the orthodontic treatment and to guide the impacted maxillary canines to their correct anatomical positions. The authors report that an iatrogenic root resorption of the maxillary lateral incisors, which is caused by a direct root contact between teeth during the active relocating procedure, can be minimized by using double-archwire mechanics. The optimal overbite, overjet, and occlusal interdigitation were achieved after the orthodontic treatment. The facial balance was also improved. Active orthodontic treatment lasted 26 months, and the results remained stable for 13 months after the removal of orthodontic appliances. This report also shows that the gingival margins of the relocated maxillary canines can be established without postorthodontic periodontal procedures when effective orthodontic mechanics are utilized to retain the canines in the alveolar bone and minimize any contact of the roots with gingival tissues during active relocation of the impacted maxillary canines.

    View details for PubMedID 18834008

  • Cone-beam computed tomography (CBCT) in clinical practice Pacific Coast Society of Orthodontists Bulletin Huang, J. C., Choo, H., Mah, J. K. 2008: 18-22

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